The present invention relates to the art of dyeing textiles with vat or sulfur dyes. More particularly, the invention relates to an improvement in fixing such vat or sulfur dyes which are present in reduced form on a fabric or textile in order to develop and improve the color characteristics of the dye on the fabric and to improve the color fastness of the dyed fabric. More particularly, the invention comprises contacting the dye in its reduced form with an aqueous solution of selected bromate or iodate and an aklali metal or ammonium vanadate.